Structure of Matter

What is Matter?

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2. Particles are in constant motion.3. Particles have spaces between them. The spaces

are much larger than the particles themselves.4. Particles are attracted to each other by

electrostatic forces.

Everything in the Universe can be classified as either matter or energy! So what is matter?

Matter is anything that has mass and occupies a volume.Matter is the “stuff” the Universe is made of

A Kaboom Key Concept!1. All matter is composed of very tiny particles

Define matter:

This is the first statement of the Particle Model of Matter.

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As temperature , the average energy of the particles

Particles are in constant motion . . .

The energy of the particles in matter determines particle motion and affects the how far apart the particles are from each other.

We can think of particle energy as TEMPERATURE.

The temperature determines

increasesincreases

the phase or state of the matter

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Three Phases of Matter

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Adding heat allows particles to overcome the attractive forces that pull them together.

Add heat

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Solids – definite volume and shape; particles packed in fixed positions; particles can only vibrate back and forth

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Liquids – definite volume but indefinite shape; particles close together but not in fixed positions; particles are free to move (rotate)

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Gases – neither definite volume nor definite shape; particles are at great distances from one another; particles are free to move (translate)

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Plasma – a plasma is an ionized gas. Plasma shares similar characteristics to gases.

A plasma is also a very good conductor of electricity and is affected by magnetic fields.

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Water phase changes

Temperature remains __________during a phase change.

constant

Heating Curve for Water (a pure substance)

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Phase change diagram

Exothermic(heat released)

Endothermic(heat absorbed)

Vaporization or boiling

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Physical changes . . .

change a substance WITHOUT changing its chemical makeup.

After a physical change, you still have the same substance, it is just in a different form.

Examples:

boiling, freezing, melting, condensation

dissolving

split, crack, crush etc

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Physical properties ..are qualities which can be observed without changing the substance’s composition.

For example:

boiling point, freezing point, melting point

color

density

solubility

hardness

malleability, ductility

conductivity

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Chemical changes Substances are broken down in chemical reactions and new substances are made.Example - Burning hydrogen (H2) with oxygen (O2) gives H2O.

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Chemical Properties describe the how substances react chemically. For example:

Metals react in acid to produce H2 gas

Zn (s) + HCl (aq) H2 (g) + ZnCl2 (aq)

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In a CHEMICAL CHANGE, the composition of the original substance(s) is altered.

The process of chemical change is described as a chemical reaction.

REACTANTS PRODUCTS

Different substances are present at the end of the chemical change. The atoms in the reactants are rearranged to make new and different products.

chemical change

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Signs of a Chemical Change

Color change Heat Light Gas Produced (not from boiling!) Precipitate – a solid formed by

mixing two liquids together

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Physical vs. Chemical Properties

Examples

melting point

flammable

density

magnetic

tarnishes in

air

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Examples

melting point

flammable

density

magnetic

tarnishes in

air

physical

chemical

physical

physical

chemical

Physical vs. Chemical Properties

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Physical vs. Chemical Changes

Examples:

rusting iron

dissolving in

water

burning wood

melting ice

grinding spices

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Physical vs. Chemical Changes

Examples:

rusting iron

dissolving in

water

burning wood

melting ice

grinding spices

chemical

physical

chemical

physical

physical